Yeah that's what they've done this year. The voucher codes counted for the 15 month promo, but they don't count them for the PS Store credit promos.I think the restriction was for Spend X get Y deals. Redeeming a PSN card didn't count because you technically didn't spend anything on the store. The 15 for 12 month deal wasn't based on spend, so I think that's why it still counted.
